You can perform your own spine test on your store-bought rods by holding them at about a 45-degree angle with the handle butt on the floor. Place the open palm of one hand about ¾ or slightly more towards the top of your rod and then use a finger or 2 on your other hand to apply some pressure on the middle of your rod to make it bend. You can try to turn the rod slightly with the fingers applying the pressure making the rod load up. You will feel it turn and kind of jump or slip onto the same spot over and over. It is a bit tricky at first, but when you get the hang of it, you will want to test every rod you have to see if it was built on the spine. If the guides aren’t line up along the bend of the rod, then you have a rod that failed the spine test. The first personal rod of mine I checked was a $350 muskie stick. Guess what? It was not built on the spine! The guides were off to the side when the rod found it’s natural bend. Wrong, wrong wrong! The horror!! I’m afraid I will find the same result on every single factory-built rod I own when I have time to check them all.
What’s the big deal, you ask? Well, when the rod is built improperly, it will have a tendency to try and roll a bit to that position when under load. When you are fishing a nice fish or snagged up, you might notice your head wanting to flip slightly one way or the other. Paul’s theory is that when someone finds a “favorite” rod out of a few of the same type they may have owned, it might be because that rod was built properly by pure luck and the rod is working how it is supposed to. Most of us would not even realize why a particular rod has a better feel or seems easier to work and use, but that would likely be the biggest reason.